1. Field of the Invention
The present invention relates to a laser sight, and in particular to a twin-beam laser module which is lightweight, handy, easy to adjust, and easy to use.
2. Description of the Related Art
In the ever-popular semiconductor laser device industry, the laser beam projected on an object forms a light spot, which is usually used for laser pointers or laser sights. Considering a laser sight that is used with shooting equipment, for example, when aiming, a user first presses his cheeks against the gun butt, and then uses the peep hole and sights to aim at a target. The aim is often hampered by the action of pressing the cheek against the gun butt. When different parts of the cheek are pressed against the gun butt, the angle of the line of sight passing through the peep hole will be affected. Consequently, the impact point would be affected, thereby adversely impacting the accuracy of the aim.
For those guns that require quick aiming, the aim by connecting peep hole and front sight can be troublesome for users. Therefore, a couple of laser sights for assistive quick aiming have been seen in the market. In particular, to prevent shooters from exposing their positions when aiming at night, a laser sight with twin-beam laser has been introduced into the market. The laser sight is integrated with the line of sight formed by peep hole and front sight, and the x-, y-, and z-axis directions of the twin-beam laser are simultaneously adjusted by a control knob so as to quickly assist in aiming.
FIGS. 1A and 1B illustrate a conventional a laser sight with a twin-beam laser module, comprising a housing 10, a first cylindrical body 12, and a second cylindrical body 14. The housing 10 comprises a first accommodating space 102 and a second accommodating space 104, three first screw holes 106 and three second screw holes 108. The first screw holes 106 and the second screw holes 108 are connected through the first accommodating space 102 and second accommodating space 104, respectively. The opposite ends of the first cylindrical body 12 are provided with a first focusing lens assembly 16 and an infrared module 18, respectively. Also, the first cylindrical body 12 is provided with three third screw holes 122, each of which is correspondingly aligned with one of the first screw holes 106. Opposing ends of the second cylindrical body 14 are provided with a second focusing lens assembly 20 and green (or red) laser module 22, respectively. The second cylindrical body 14 is provided with three fourth screw holes 142, each of which is correspondingly aligned with one of the second screw holes 108 to form a continuous channel throughout.
During assembled, the first cylindrical body 12 and the second cylindrical body 14 are mounted into the first and second accommodating spaces 102 and 104, respectively. Further, a plurality of bolts (not shown here) are inserted into the three first screw holes 106, the three second screw holes 108, the three third screw holes 122, and the three fourth screw holes 142. When the apparatus is being adjusted, the bolts described above are used to adjust the axial direction of the first cylindrical body 12, such that the first infrared module 18 emits a first laser beam extending through the first focusing lens assembly 16 to project on to a pre-determined spot. The first laser beam is then used as a reference point, and the bolts described above are then used to adjust the axial direction of the second cylindrical body 14, so that the green (or red) laser module 22 emits a second laser beam extending through the second focusing lens assembly 20 parallel to the first laser beam.
The mechanism described above has a complicated construction. In addition, the first cylindrical body 12 and the second cylindrical body 14 require a very tedious adjustment to align the laser beams to be projected in a parallel manner. Consequently, the calibration of the projected beams is difficult, thereby increasing the production cost. Also, with increasing demand of thin, compact, and portable products, it is important to further simplify the structure and to reduce the volume.
Thus, there still remains a need for a twin-beam laser module for use with laser sights, which overcomes the drawbacks mentioned above.